Underframe for carriages



July 21,1936. 54m 29 18280 UNDERFRAME FOR CARRIAGES" Filed July 7. 1933Patented July 21*, 1936 UNITED STATES PATENT OFFICE UNDERFBAME FOROARRIAGES Steffen Mob], Copenhagen, Denmark Application July '1, 1933,Serial No. 679,431-

' In Germany July 8, 1932 Claims.

5 to be used partly as a unit under a carriage throughout the entirelength of the same, and partly as two or more bogies situated below thebody of the carriage and adapted, perhaps, to rotate sideways relativelythereto. The constantly increasing carrying capacity required duringrecent years for such carriages, whether the same are to run on ordinaryroads or on railroads, necessitates an increase in the number of pairsof wheels in the underframe or underframes, partly with a view to thecarrying capacity of the individual wheel and partly with a view to thecarrying capacity of the roads or the supporting rails.

The present invention has for its object to provide a more simple andsuitable construction of such multi-axle underframes than those knownheretofore, and according to the invention this object is to be attainedby the feature that on each side'of the frame (the carriage) the twoouterpairs of wheels, i. e. the foremost and the rearmost wheels, areresting in one arm of a two-armed lever supported by the frame andadapted to swing in a vertical plane relatively thereto, and having itsother arm linked to one end of a spring supporting the adjoiningintermediate wheel of the frame. The two extreme pairs of wheels of theframe are thus not directly spring-loaded but. indirectly, i. e. throughthe said levers by means of the springs of the intermediate wheels.

By arrangements known for instance from locomotive underframes 'such anunder-frame with more than two pairs of wheels may be caused to behaveexternally, like one single pair stance not precluded by theuse of theunderframe as a bogie under a carriage body, if the 50 latter rests onthe frame through an ordinary spherical head at the centre of the bogie.The

possibility of an irregular pitching of the bogiewill on the contrary beprecluded, if the weight of the carriage body be transmitted to thebogie 55 partly through a spherical head at a certain distance from thecentre thereof (towards the front or rear end), and partly through aslide or roller surface-at a certain distance from the centre of thebogie but to the other side thereof. Hereby the advantage is evidentlysimultaneously at- 5 tained that the load will be distributed moreuniformly than otherwise over the frame of the bogie, whereby thebending moments in the same will be reduced. Also other arrangementsthan the one described, but in accordance with the frame a supporting oneach of its long sides 25 two bearing brackets b pointing downward.These bracket bearings form bearings each for one of the two-armedlevers 0 c with pivot pin d. In each of these two-armed levers the arm cthat points away from the centre of the bogie 30 supports one of thefront or rear wheels e, e of the underfram'e, and the inner arm 0 is bymeans of a link bar f linked to one end of a plate spring 9 whichsupportsthe bearing h for an intermediate wheel i.- The two lever arms cand c are 35 given such lengths that the load on the frame a isdistributed uniformly on all three wheels e, e and i, and it is seendirectly that all these wheels are uniformly spring-loaded by one singlespringg common to all three wheels. 40

A modified form of the construction shown in Fig. 1 is illustrated inFig.2, in which two directly spring-loaded intermediate wheels 1', i areused. The two springs g, g have then, in known manner, their adjacentends linked to a small balance a, which is pivoted on a bracketsupported by the frame a. Provided that the lever arms c and c besuitably selected, this arrangement will ensure apreferably uniformloading of all four wheels, even if the road surface (the track) berough. The arrangement may be further varled by the insertion of stillmore intermediate e and i will be uniformly loaded. All the shaftstogether will further act as one single shaft, 1. e. the above mentionedstability with respect to arbitrary "pitching of the frame a of theunderframe will be lacking. If desired, however, this stability can besecured simply by preventing the possibility of any rocking motion forone of the said equalizing balances 7, which in practice will mean thatone of these balances is to be omitted entirely, the two adjoiningspring ends being then hinged directly to the frame a. If this is donefor instance in the construction shown in Fig. 2, it will be seendirectly that the entire underframe will act as if it were only composedof two pairs of separately spring-loaded wheels. Thereby a fullstability against any arbitrary pitching will be attained.

Another possibility of attaining such a stability without deviating fromthe principal idea underlying the invention appears from Fig. 3, inwhich the underframe shown in Fig. 1 is supplemented by a fourth pair ofwheels is supported directly by two springs I hinged independently tothe frame a. Such an arrangement, which consequently will act as if twoseparately and directly springloaded wheel axles were provided, will forinstance be very suitable for shunting locomotives and similar carriagesof a very compact construction. I

The railroad carriage shown in Fig. 4 is a construction of thearrangement shown in Fig. 1

and consists of a frame a fitted at each end with an incision a1 and atthe centre with'an incision m, which latter extends all the -way down tothe bottom edge of the frame, but is closed thereby means of splice barsn. At each end of the frame a bearing bracket an is bolted thereto forthe lever with unequal arms Cl, 02 supporting the end wheels e. Besides,I have here like in Fig. 1 the link members I, the spring 9, the bearingh and the intermediate wheel i. The central wheel i with its axle can bebrought into position by being inserted from below, after. the splicebars 1; have been removed, and the two end wheels can be removed afterthe bearing bracket a: has been loosened, and the connection between thelink member and the spring 9 has been removed.

The connections required for maintaining constant the mutual horizontaldistances between the wheel axles are omitted in all the figures of thedrawing, since such connections are well known as a substitute for thefixed guides for the axle boxes ordinarily used on railroad bogies.

In a bogie like the one here referred to it is possible to use aone-sided braking on the wheels supported by the levers as the brakereactions on the axle are taken up by the levers c Such a one-sidedbraking offers constructional advantages, for instance that the lengthof the bogie frame a can be made essentially shorter than the'lengthrequired when a two-sided braking is used, and the one-sided brakingrequires merely the wheel axles to be so heavily dimensioned that theycan resist the bending moment to which they are exposed in consequenceof the one-sided brake pressure.

The arrangement shown in Fig. 5 of the levers c a relatively to thewheels, 1. e. with the levers disposed inside of the wheels, is suitablefor locomotives, as the springs of the latter are usually situatedinside of the wheels.

The arrangement shown in Fig. 6, on the con- 'trary, is suitable forrailway carriages, because or railroad track can only form small angleswith the horizontal plane of the frame a.

As to the constructions shown for bogies fo railroad carriages, itshould be noted that the desirability of fitting such bogies with agreater number of axles than the two that are ordinarily used at thepresent time has lately been increased considerably, after the,successful experiments made with the use of automobile wheels (wheelswith inflated tyres) for railroad traflic. Such wheels are in factunableto transmit the same great pressures to the rails as the ordinaryrailroad wheels of steel.

When using the underframe here referred to for automobiles one or moreof the pairs of wheels of the bogie may be driven by the motor, ifdesired. For driving one of the end axles the arrangement of the levers0 c shown in Fig. 7 may be suitable, provided that the axle casing bejournalled in the levers by means of inserted rubber bushings of knownnature, which allow the requisite universal motion. If on the other handthe underframe is arranged in such a manner that the end wheels aremerely supporting wheels, it will in some cases be preferable to steerthe same together with the other steering wheels as indicated in Fig. 8,as otherwise for three or more consecutive axles for non-steered wheels,owing to the skidding that cannot be avoided in such a construction,there might occur a greater wear of rubber than desirable or permissiblefrom a trafiic point of view. The steering of the drivingwheels shown inFig. 7 may also be effected in known manner, even if the constructionmight thereby become somewhat more complicated.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is:

1. In an underframe for carriages having a group of spring loaded wheelson each side thereof adjacent a longitudinal frame member, thecombination of two rigid levers for each group, each directly supportedat one end by the bearing of one of the outermostwheels of the group, aspring connected to the other end of each of the said levers and carriedpractically at its center by the bearing of an intermediate wheel of thegroup, means pivoting each lever intermediate its ends to the adjacentframe member in such a manner that its movement is restricted to alongitudinal vertical plane, whereby each outermost wheel bearing ispivotally guided in a vertical circular arc.

2. In an underframe for carriages having a group of three spring loadedwheels on each side thereof adjacent a longitudinal frame member, thecombination of two rigid levers for each group, each directly supportedat one end by the bearing of one of the outermost wheels of the group, aspring joining the other ends of each of the said levers and carriedpractically at its center by the bearing of the center wheel of thegroup, means pivoting each lever intermediate its ends to the adjacentframe member in such a manner that its movement is restricted to alongitudinal vertical plane, whereby each outermost wheel bearing ispivotally guided in a vertical circular arc.

3. In an underframe for carriages having a group of four spring loadedwheels on each side thereof, adjacent a longitudinal frame member, thecombination of two rigid levers for each group each directly supportedat one end by the bearing of one of the outermost wheels of the group, aspring connected to the other end of each of the said levers and carriedpractically at its center by the bearing of an intermediate wheel of thegroup, means pivoting each lever intermediate its ends to the adjacentframe member in such a manner that its movement is restricted to alongitudinal vertical plane, whereby each outermost wheel bearing ispivotally guided in a vertical circular arc, the two said intermediatewheelcarried springs having their remaining ends adjacent and directlyconnected to the longitudinal frame member.

4. In an underframe for carriages having 'a group of four spring loadedwheels on each side thereof adjacent a longitudinal frame member, thecombination of two rigid levers for each group, each directly supportedat one end by the hearing of one of the outermost wheels of the group, aspring connected to the other end of each of the said levers and carriedpractically at its center by the bearing of an intermediate wheel of thegroup, means pivoting each lever intermediate its ends to the adjacentframe member in such a manner that its movement is restricted to alongitudinal vertical plane, whereby each outermost wheel bearing ispivotally guided in a vertical circular arc, and a lever pivoted at itscenter to the frame and having two equal arms, the two remaining andadjacent ends of the two springs carried by the intermediate wheelsbeing each connected to one end of said last mentioned lever.

5. In an underframe for carriages having a group of spring loaded wheelson each side thereof adjacent a longitudinal frame member, thecombination of two rigid levers for each group, each directly supportedat one end by the bearing of one of the outermost wheels of the group, aspring connected to the other end of each of said levers and carriedpractically at its center by the bearing of an intermediate wheel of thegroup, means pivoting each lever intermediate its ends to the adjacentframe member in such a manner that its movement is restricted to a1ongitudinal vertical plane, whereby each outermost wheel bearing ispivotally guided in a vertical circular arc, and an additional springsecured to the frame on each side, a wheel supporting the said springand positioned next to one of the above named outermost wheels for thepurpose of preventing any irregular pitching of the frame.

STEFFEN MGHL.

